foo.cc: In function 'void daysum()':
foo.cc:54:19: warning: self-comparison always evaluates to true [-Wtautological-compare]
   54 |         else if(lm==lm){
      |                 ~~^~~~
foo.cc:78:19: warning: self-comparison always evaluates to true [-Wtautological-compare]
   78 |         else if(lm==lm){
      |                 ~~^~~~
foo.cc: In function 'int main()':
foo.cc:91:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   91 |     scanf("%d %d %d",&fy,&fm,&fd);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:92:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   92 |     scanf("%d %d %d",&ly,&lm,&ld);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc: In function 'int checkday(int, int)':
foo.cc:38:12: warning: 'daynum' may be used uninitialized in this function [-Wmaybe-uninitialized]
   38 |     return daynum;
      |            ^~~~~~
foo.cc: In function 'void daysum()':
foo.cc:72:15: warning: 'dl' may be used uninitialized in this function [-Wmaybe-uninitialized]
   72 |             dl+=checkday(fy,fm)-fd;
      |             ~~^~~~~~~~~~~~~~~~~~~~

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